High ground doesn't matter in SC2 nearly as much as it did in BW. Units would miss around 70% of the time when they shot at high ground (supposed to be 50% but it's been tested many times and ended up being around 70) in BW. In SC2, if I have roughly the same size army on the low ground, I push up anyway because I rely on the fact that I usually have better micro. I'd never do that in BW.

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